In a copper plating experiment , the difference between final and initial masses of the cathode is measured carefully and is found to be `16.43` g . The time duration of electrolysis is noted to be 4000 s . The steady reading of current in an ammeter placed in series with the voltameter is `12.6` A . what is the error in the ammeter reading ?
(F = 96485 C `mol^(-1)` , relative atomic mass of Cu = `63.54` )